title: Timing of colonoscopy after resection for colorectal cancer: are we looking too soon?
abstract: BACKGROUND
  Based on current National Comprehensive Cancer Network guidelines, colonoscopic surveillance after colorectal cancer resection should begin at 1 year.
  
  
  OBJECTIVE
  The aim of this study was to determine whether the incidence of cancer or advanced polyp detection rate was high enough to justify colonoscopy at 1 year.
  
  
  METHODS
  The Ochsner Clinic Tumor Registry Database was queried for patients who underwent a segmental colectomy or proctectomy between 2002 and 2010. Patients who had a preoperative colonoscopy and at least 1 documented postoperative colonoscopy were included. We considered new cancer or polyps of ≥1 cm as missed on the preoperative colonoscopy. Patients with an identified genetic trait causing a predisposition to colorectal cancer were excluded.
  
  
  RESULTS
  Five hundred twelve patients underwent resection, and 155 met our inclusion criteria. The average age was 64 years, and 53% patients were male. There were 32.9% with stage I disease, 35% with stage II disease, 27.1% with stage III disease, and 5.2% with stage IV disease. Of these patients, 52.2% had a right colectomy, 7.1% had a left colectomy, 16.8% had a sigmoid colectomy, 22% had a low anterior resection, and 1.3% had a transanal resection. The average time to first postoperative colonoscopy was 478 days (SD ±283 days). Twenty-four patients had adenomatous polyps detected on their first surveillance colonoscopy, but only 5 (3.2%) polyps were ≥1 cm, and there was no correlation between stage of cancer and finding a polyp. No new cancers were detected, but 3 (1.9%) had an anastomotic recurrence.
  
  
  CONCLUSIONS
  The performance of surveillance colonoscopy at 1 year resulted in the detection of only 5 missed polyps ≥1 cm and no metachronous cancers. Anastomotic recurrences were rare, and the majority were in patients who had rectal cancer that could be evaluated by in-office flexible sigmoidoscopy. Extending the time to first colonoscopy appears to be safe and would help conserve valuable resources, including physician and facility time, which is imperative in the current health care climate.
authors.affiliation: 1 Department of Colon and Rectal Surgery, Ochsner Clinic Foundation, New Orleans, Louisiana 2 The University of Queensland School of Medicine, Ochsner Clinical School, New Orleans, Louisiana.
authors.forename: M M
authors.initials: MM
authors.lastname: Cone
authors.forename: D E
authors.initials: DE
authors.lastname: Beck
authors.forename: T E
authors.initials: TE
authors.lastname: Hicks
authors.forename: J D
authors.initials: JD
authors.lastname: Rea
authors.forename: C B
authors.initials: CB
authors.lastname: Whitlow
authors.forename: H D
authors.initials: HD
authors.lastname: Vargas
authors.forename: D A
authors.initials: DA
authors.lastname: Margolin
mesh_terms: D000236:Adenoma / Q000175:diagnosis; D003110:Colonic Neoplasms / Q000175:diagnosis; D003111:Colonic Polyps / Q000175:diagnosis*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D011182:Postoperative Care; D012042:Registries; D013997:Time Factors